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1.
Ann Dermatol Venereol ; 147(5): 387-395, 2020 May.
Artigo em Francês | MEDLINE | ID: mdl-32248967

RESUMO

The terms deodorants and antiperspirants very frequently used interchangeably despite the fact that they employ completely different active substances and mechanisms of action. Antiperspirants are necessarily deodorants due to the lack of substrate to decompose. They nevertheless represent a group of very specific substances that create particular problems due to the presence of aluminium chlorohydrate, or ACH, (Al2(OH)5Cl, 2H2O), aluminium sesquichlorohydrate and aluminium-zirconium complex, which, after hydrolysis, causes intense acidification of the skin, hence the importance of inclusion of emollients and pH regulators in formulations. Moreover, systemic aluminium is thought to be genotoxic and to promote breast cancer, and it is thus at the centre of numerous scientific controversies. Nevertheless, its potential toxicity following topical application is related to its ability to penetrate skin, which is as yet poorly understood but considered very low, a fact that may provide some degree of reassurance regarding its use in cosmetic products. Its role in Alzheimer's disease has not been proven. On the other hand, zirconium salts are considered toxic and are partly regulated in Europe. The problems associated with deodorants are those arising from the presence of antiseptics (triclosan, usnic acid) capable of inducing bacterial resistance, but more particularly, the presence of axillary dermatitis due to the allergenic potential of the fragrances and essential oils used (e.g. isoeugenol, citronellal, lyral, cinnamic aldehyde, etc.).


Assuntos
Antiperspirantes , Desodorantes , Antiperspirantes/efeitos adversos , Antiperspirantes/química , Desodorantes/efeitos adversos , Desodorantes/química , Humanos
2.
Ann Dermatol Venereol ; 144(10): 638-644, 2017 Oct.
Artigo em Francês | MEDLINE | ID: mdl-28823805

RESUMO

Practically all currently available self-tanning products have as their active ingredient dihydroxyacetone (DHA), which may or may not be combined with erythrulose, tyrosine derivatives, and occasionally a naphthoquinone. The resulting skin tone, which resembles a natural tan, is due to chemical combination of the DHA with amino acids in the skin through the Maillard reaction. Polymer pigments known as melanoidins are formed and are fixed in the stratum corneum, where they remain until corneocyte desquamation occurs. The colouring thus achieved is semi-permanent and is well tolerated by skin. While the formulation of such products is complex and their storage difficult, no other substances provide more satisfactory or more lasting results.


Assuntos
Cosméticos/farmacologia , Di-Hidroxiacetona/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Composição de Medicamentos , Humanos
3.
Pharm Biol ; 50(10): 1269-75, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22873798

RESUMO

CONTEXT: Medicinal plants are well known for their use in traditional folk medicine as treatments for many diseases including infectious diseases. OBJECTIVE: Six Brazilian medicinal plant species were subjected to an antiviral screening bioassay to investigate and evaluate their biological activities against five viruses: bovine herpesvirus type 5 (BHV-5), avian metapneumovirus (aMPV), murine hepatitis virus type 3, porcine parvovirus and bovine respiratory syncytial virus. MATERIALS AND METHODS: The antiviral activity was determined by a titration technique that depends on the ability of plant extract dilutions (25 or 2.5 µg/mL) to inhibit the viral induced cytopathic effect and the extracts' inhibition percentage (IP). RESULTS: Two medicinal plant species showed potential antiviral activity. The Aniba rosaeodora Ducke (Lauraceae) extract had the best results, with 90% inhibition of viral growth at 2.5 µg/mL when the extract was added during the replication period of the aMPV infection cycle. The Maytenus ilicifolia (Schrad.) Planch. (Celastraceae) extracts at a concentration of 2.5 µg/mL exhibited antiviral activity during the attachment phase of BHV-5 (IP = 100%). DISCUSSION AND CONCLUSION: The biomonitored fractionation of the active extracts from M. ilicifolia and A. rosaeodora could be a potential tool for identifying their active compounds and determining the exact mechanism of action.


Assuntos
Antivirais/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Doenças dos Animais/tratamento farmacológico , Doenças dos Animais/virologia , Animais , Antivirais/administração & dosagem , Antivirais/isolamento & purificação , Brasil , Bovinos , Relação Dose-Resposta a Droga , Herpesvirus Bovino 5/efeitos dos fármacos , Lauraceae/química , Maytenus/química , Medicina Tradicional , Metapneumovirus/efeitos dos fármacos , Camundongos , Extratos Vegetais/administração & dosagem , Suínos , Replicação Viral/efeitos dos fármacos
4.
J Clin Endocrinol Metab ; 77(5): 1215-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8077314

RESUMO

Lignans are a group of phytochemicals shown to have weakly estrogenic and antiestrogenic properties. Two specific lignans, enterodiol and enterolactone, are absorbed after formation in the intestinal tract from plant precursors particularly abundant in fiber-rich food and are excreted in the urine. We evaluated the effect of the ingestion of flax seed powder, known to produce high concentrations of urinary lignans, on the menstrual cycle in 18 normally cycling women, using a balanced randomized cross-over design. Each subject consumed her usual omnivorous, low fiber (control) diet for 3 cycles and her usual diet supplemented with flax seed for another 3 cycles. The second and third flax cycles were compared to the second and third control cycles. Three anovulatory cycles occurred during the 36 control cycles, compared to none during the 36 flax seed cycles. Compared to the ovulatory control cycles, the ovulatory flax cycles were consistently associated with longer luteal phase (LP) lengths (mean +/- SEM, 12.6 +/- 0.4 vs. 11.4 +/- 0.4 days; P = 0.002). There were no significant differences between flax and control cycles for concentrations of either estradiol or estrone during the early follicular phase, midfollicular phase, or LP. Although flax seed ingestion had no significant effect on LP progesterone concentrations, the LP progesterone/estradiol ratios were significantly higher during the flax cycles. Midfollicular phase testosterone concentrations were slightly higher during flax cycles. Flax seed ingestion had no effect on early follicular phase concentrations of DHEA-S, PRL, or sex hormone-binding globulin. Our data suggest a significant specific role for lignans in the relationship between diet and sex steroid action, and possibly between diet and the risk of breast and other hormonally dependent cancers.


Assuntos
Dieta , Ciclo Menstrual , Plantas Comestíveis , 4-Butirolactona/análogos & derivados , 4-Butirolactona/urina , Adulto , Estrogênios/urina , Feminino , Hormônios/sangue , Humanos , Lignanas/urina , Fase Luteal , Concentração Osmolar
5.
Neurobiol Aging ; 22(3): 413-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11378247

RESUMO

Inflammatory processes are thought to be important contributors to the pathogenesis of Alzheimer's disease (AD). alpha1-antichymotrypsin (ACT) is a proteinase inhibitor characteristic of acute-phase inflammation and has been identified in amyloid plaques. We analyzed the plasma ACT levels in a sample of subjects with late-onset AD and correspondent controls. Plasma ACT was higher in AD patients (62.8 +/- 20.2 mg/dl) than in controls (58.8 +/- 18.1 mg/dl), but not significantly (P = 0.13). In the AD patients regression analysis showed a positive linear relationship between ACT levels and duration of the disease (P = 0.037). Increased ACT concentrations (64.6 +/- 21.2 mg/dl) were also found in patients with greater cognitive impairment (MMSE scores < 20), but since this factor depends on the duration of the disease as well, our present data seem to indicate a complex relationship involving elevated ACT levels, disease duration and cognitive impairment. Plasma ACT was found to differ significantly according to APOE genotypes (P = 0.017), the highest levels being associated to E3-E3 homozygotes (66.1 +/- 17.8 mg/dl) and the lowest to E4-E3 subjects (53.1 +/- 18.2 mg/dl). In patients not carrying APOE*4 allele the ACT levels were higher than in controls (P = 0.014), and the relationship between ACT and disease duration was stronger than that observed in the total AD sample (P = 0.003), but it was absent in those carrying APOE*4 (P = 0.67). Taken together our results seem to suggest that inflammation is a relevant factor in AD pathogenesis for subjects with E3-E3 and E3-E2 genotypes but less important for APOE*4 carrying subjects.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Apolipoproteínas E/genética , alfa 1-Antiquimotripsina/sangue , Idoso , Idoso de 80 Anos ou mais , Alelos , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Apolipoproteína E4 , Feminino , Genótipo , Humanos , Masculino , Fenótipo , Polimorfismo Genético/genética , alfa 1-Antiquimotripsina/genética
6.
Am J Clin Nutr ; 47(1): 57-60, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3122554

RESUMO

Lactose digestion from and tolerance to lactose-containing beverages consumed with food was evaluated in 12 lactase-deficient subjects by breath-hydrogen techniques. Peak hydrogen production after a milk-based food supplement was delayed 2 h as compared with a lactose solution. Addition of a breakfast meal further delayed peak hydrogen production by 1 h. Hydrogen production was significantly lower (p less than 0.03) for the first 4 h after ingestion of the supplement plus meal compared with the supplement alone. Nine subjects experienced intolerance symptoms after consumption of the supplement alone but only three experienced them after consumption of the meal plus supplement. Severity of symptoms was significantly reduced with the ingestion of the supplement compared with an equal lactose load and was further reduced with the consumption of food, presumably due to delayed gastric emptying. Thus, lactose malabsorbers should consume food simultaneously with lactose-containing beverages to reduce intolerance symptoms.


Assuntos
Dieta/efeitos adversos , Intolerância à Lactose/prevenção & controle , Lactose/metabolismo , Adulto , Animais , Bebidas/efeitos adversos , Testes Respiratórios , Dióxido de Carbono/análise , Feminino , Alimentos Fortificados , Humanos , Hidrogênio/análise , Intolerância à Lactose/metabolismo , Teste de Tolerância a Lactose/métodos , Masculino , Pessoa de Meia-Idade , Leite , Fatores de Tempo
7.
Am J Clin Nutr ; 53(5): 1253-8, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2021132

RESUMO

Lactose in yogurt is better digested than lactose in other dairy foods by lactase-deficient individuals, in part because of intraintestinal activity of yogurt microbial beta-galactosidase (beta-gal). The survival and activity of yogurt beta-gal depend on gastrointestinal transit, pH, and viability of the yogurt culture. To evaluate the ability of yogurt beta-gal to digest lactose when yogurt is consumed with food or with additional lactose, 22 healthy lactose-maldigesting individuals were fed 10 test meals. Results of breath-hydrogen expiration, incidence of symptoms, and enzyme and lactose content of gastric aspirates indicate that the consumption of a meal with yogurt does not inhibit, and may slightly improve, lactose digestion from yogurt. However, yogurt beta-gal appears unable to assist in the digestion of additional lactose beyond that normally present in yogurt.


Assuntos
Digestão , Intolerância à Lactose/metabolismo , Lactose/metabolismo , Iogurte , Adulto , Animais , Feminino , Alimentos , Humanos , Masculino , Leite/metabolismo
8.
Am J Clin Nutr ; 70(3 Suppl): 459S-463S, 1999 09.
Artigo em Inglês | MEDLINE | ID: mdl-10479218

RESUMO

Dietary guidelines recommend the consumption of whole grains to prevent chronic diseases. Epidemiologic studies support the theory that whole grains are protective against cancer, especially gastrointestinal cancers such as gastric and colon can-cer, and cardiovascular disease. Components in whole grains that may be protective include compounds that affect the gut environment, such as dietary fiber, resistant starch, and oligosaccharides. Whole grains are also rich in compounds that function as antioxidants, such as trace minerals and phenolic compounds, and phytoestrogens, with potential hormonal effects. Other potential mechanisms whereby whole grains may protect against disease include binding of carcinogens and modulation of the glycemic response. Clearly, the range of protective substances in whole grains is impressive and advice to consume additional whole grains is justified. Further study is needed regarding the mechanisms behind this protection so that the most potent protective components of whole grains will be maintained when developing whole grains into acceptable food products for the public.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Fibras na Dieta/uso terapêutico , Grão Comestível/uso terapêutico , Neoplasias/prevenção & controle , Fitoterapia , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Fibras na Dieta/administração & dosagem , Fibras na Dieta/classificação , Grão Comestível/classificação , Análise de Alimentos , Guias como Assunto , Humanos , Neoplasias/epidemiologia
9.
Am J Clin Nutr ; 46(4): 636-40, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3116836

RESUMO

Lactose digestion from and tolerance to flavored and frozen yogurts, ice cream, and ice milk were evaluated (20 g lactose/meal) in lactase-deficient subjects by use of breath hydrogen techniques. Unflavored yogurt caused significantly less hydrogen production than milk (37 vs 185 delta ppm X h, n = 9). Flavored yogurt was intermediate (77 delta ppm X h). Subjects were free of symptoms after consuming flavored and unflavored yogurts. Of seven commercial yogurts tested, all contained significant levels of microbial beta-galactosidase (beta-gal). In addition, eight subjects were fed meals of milk, ice milk, ice cream, and frozen yogurts with and without cultures containing high levels of beta-gal. Peak hydrogen excretion after consumption of frozen yogurt with high beta-gal was less than one-half of that observed after the other five test meals and intolerance symptoms were absent. Tolerance to frozen yogurt, produced under usual commercial procedures, was found to be similar to that of ice milk and ice cream.


Assuntos
Laticínios , Sorvetes , Intolerância à Lactose/metabolismo , Lactose/metabolismo , Leite/metabolismo , Iogurte , Adulto , Animais , Humanos , Intolerância à Lactose/enzimologia , Masculino , Pessoa de Meia-Idade , beta-Galactosidase/análise
10.
Am J Clin Nutr ; 60(1): 122-8, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8017326

RESUMO

Lignans and isoflavonoid phytoestrogens, produced from plant precursors by colonic bacteria, may protect against certain cancers. We examined the effects of flaxseed consumption on urinary lignans and isoflavonoids. Eighteen women consumed their usual omnivorous diets for three menstrual cycles and their usual diets supplemented with flaxseed powder (10 g/d) for three cycles in a randomized crossover design. Three-day urine samples from follicular and luteal phases were analyzed for lignans and isoflavonoids by isotope-dilution gas chromatography--mass spectrometry. Excretion of the lignans enterodiol and enterolactone increased with flaxseed from 1.09 +/- 1.08 and 3.16 +/- 1.47 to 19.48 +/- 1.10 and 27.79 +/- 1.50 mumol/d, respectively (P < 0.0002). Enterodiol and enterolactone excretion varied among subjects in response to flaxseed (3- to 285-fold increase). There were no differences in excretion of isoflavonoids (daidzein, genistein, equol, and O-desmethylangolensin) or the lignan matairesinol with flaxseed. Excretion was not altered by phase of menstrual cycle or duration of flaxseed consumption.


Assuntos
Dieta , Isoflavonas/urina , Lignanas/urina , Pré-Menopausa/metabolismo , Sementes , Administração Oral , Adulto , Peso Corporal , Fibras na Dieta , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ciclo Menstrual/metabolismo , Pós
11.
Am J Clin Nutr ; 60(6): 895-9, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7985630

RESUMO

Midfollicular and midluteal dietary intakes of 18 women were evaluated between four and six ovulatory menstrual cycles. Phase lengths were established by basal body temperatures and urinary luteinizing hormone excretion. Midfollicular and midluteal diet records were collected 6-8 d after menstrual onset and 6-8 d after ovulation, respectively. Significant increases in energy [0.66 MJ (159 kcal), P = 0.003], protein (6.1 g, P = 0.02), carbohydrate (15.3 g, P = 0.04), and fat (8.6 g, P = 0.002) intakes were observed in midluteal phase when compared with midfollicular phase. Intakes of vitamin D, riboflavin, potassium, phosphorus, and magnesium also were significantly higher during midluteal phase (P < 0.05). These results support the regulation of food intake by menstrual cycle hormones and suggest that it is essential to consider phase of menstrual cycle in studies of nutrient intake performed in premenopausal women.


Assuntos
Ingestão de Energia , Ciclo Menstrual/fisiologia , Fenômenos Fisiológicos da Nutrição , Adulto , Estudos Cross-Over , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta , Proteínas Alimentares/administração & dosagem , Exercício Físico , Feminino , Humanos , Magnésio/administração & dosagem , Fósforo/administração & dosagem , Potássio/administração & dosagem , Riboflavina/administração & dosagem , Vitamina D/administração & dosagem
12.
Am J Clin Nutr ; 45(2): 432-6, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3101480

RESUMO

Lactase-deficient subjects more effectively digest lactose in yogurt than lactose in other dairy products, apparently due to yogurt microbial beta-galactosidase (beta-gal) which is active in the GI tract. We evaluated the effects of buffering capacity of yogurt, gastric pH, and microbial cell disruption on beta-gal activity and lactose digestion. Three times more acid was required to acidify yogurt than to acidify milk. Yogurt beta-gal was stable at pH 4.0 but inactivated at lower pH. When yogurt was sonicated to disrupt microbial cell structure, only 20% activity remained after incubation at pH 4.0 for 60 min. In vivo gastric pH remained greater than 2.7 for 3 h after ingestion of yogurt. Acidified milk alone or with disrupted yogurt microorganisms caused twice as much lactose malabsorption as did acidified milk containing intact yogurt microorganisms. The results provide a possible explanation for the survival of beta-gal activity from yogurt in the GI tract.


Assuntos
Laticínios , Digestão , Galactosidases/metabolismo , Lactose/metabolismo , Iogurte , beta-Galactosidase/metabolismo , Adulto , Soluções Tampão , Membrana Celular/fisiologia , Parede Celular/fisiologia , Determinação da Acidez Gástrica , Humanos , Lactobacillus/ultraestrutura , Intolerância à Lactose/metabolismo , Masculino , Sonicação , Streptococcus/ultraestrutura
13.
Am J Clin Nutr ; 54(6): 1041-6, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1957819

RESUMO

Lactose in yogurt with live bacteria is better tolerated than lactose in other dairy foods, partly because of the activity of microbial beta-galactosidase (beta-gal), which digests lactose in vivo. To evaluate the ability of different strains and species of lactic acid bacteria to digest lactose in vivo, yogurts (containing mixtures of strains of Streptococcus salivarius subsp thermophilus and Lactobacillus delbrueckii subsp bulgaricus) and fermented milks (containing individual species of S thermophilus, L bulgaricus, L acidophilus, or Bifidobacterium bifidus) that varied in microbial beta-gal activity were produced. Selected products were fed to healthy people who cannot digest lactose, and breath hydrogen production was monitored. All yogurts dramatically and similarly improved lactose digestion, regardless of their total or specific beta-gal activity. The response to fermented milks varied from marginal improvement with B bifidus milk to nearly complete lactose digestion with L bulgaricus milk. The results suggest that total beta-gal was not the limiting factor in promoting lactose digestion, perhaps because of a limited rate of intracellular substrate transport.


Assuntos
Bactérias/genética , Digestão , Lactose/metabolismo , Iogurte/microbiologia , Adulto , Animais , Fenômenos Fisiológicos Bacterianos , Contagem de Colônia Microbiana , Ingestão de Alimentos , Feminino , Humanos , Hidrogênio , Lactatos , Ácido Láctico , Lactose/análise , Masculino , Respiração , Iogurte/análise , beta-Galactosidase/análise
14.
Cancer Epidemiol Biomarkers Prev ; 4(4): 353-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7655330

RESUMO

Lignans and isoflavonoids are diphenolic compounds found in plant foods, particularly whole grains and legumes. They have been shown to have anticarcinogenic properties in animal and cell studies, and have been associated with reduced cancer risk in epidemiological studies. In order to perform further epidemiological and metabolic studies on these compounds, it is necessary to be able to monitor concentrations in biological samples. In this study, we examined the effects of consumption of flaxseed, a concentrated source of lignans, on fecal lignan excretion and evaluated the effect of high lignan consumption on fecal excretion of isoflavonoids. Thirteen women were studied for two diet periods of three menstrual cycles each in a cross-over design. During the control period, they consumed their usual diets; during the treatment period they consumed their usual diets supplemented with 10 g/day ground flaxseed. Feces were collected on days 7-11 of the last menstrual cycle in each diet period. Five-day fecal composites were analyzed for lignans and isoflavonoids by isotope dilution gas chromatography-mass spectrometry. Fecal excretion of the lignans enterodiol, enterolactone, and matairesinol increased significantly with flax consumption, from 80.0 +/- 80.0 (SD) to 2560 +/- 3100; 640 +/- 480 to 10,300 +/- 7580; and 7.33 +/- 10.0 to 11.9 +/- 8.06 nmol/day, respectively. There were no differences in fecal excretion of the isoflavonoids, daidzein, equol, genistein, and O-demethylangolensin.


Assuntos
Fezes/química , Flavonoides/metabolismo , Lignanas/análise , Pré-Menopausa/metabolismo , Sementes/metabolismo , Adulto , Peso Corporal , Dieta , Feminino , Humanos , Lignanas/classificação
15.
Cancer Epidemiol Biomarkers Prev ; 9(7): 719-25, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10919743

RESUMO

Estrogen is metabolized along two competing pathways to form the 2-hydroxylated and the 16alpha-hydroxylated metabolites. Based on proposed differences in biological activities, the ratio of these metabolites, 2-hydroxyestrogen:16alpha-hydroxyestrone (2:16alpha-OHE1), has been used as a biomarker for breast cancer risk. Women with an elevated 2:16alpha-OHE1 ratio are hypothesized to be at a decreased risk of breast cancer. Flaxseed, the most significant source of plant lignans, and wheat bran, an excellent source of dietary fiber, have both been shown to have chemoprotective benefits. Some of these benefits may be attributable to their influence on endogenous sex hormone production and metabolism. We examined the effect of flaxseed consumption alone and in combination with wheat bran on urinary estrogen metabolites in premenopausal women. Sixteen premenopausal women were studied for four feeding treatments lasting two menstrual cycles each in a randomized cross-over design. During the four feeding treatments, subjects consumed their usual diets supplemented with baked goods containing no flaxseed or wheat bran, 10 g of flaxseed, 28 g of wheat bran, or 10 g of flaxseed plus 28 g of wheat bran/day. Urinary excretion of 2-hydroxyestrogen and 16alpha-hydroxyestrone, as well as their ratio, 2:16alpha-OHE1, were measured by enzyme immunoassay. Flaxseed supplementation significantly increased the urinary 2:16alpha-OHE1 ratio (P = 0.034), but wheat bran had no effect. These results suggest that flaxseed may be chemoprotective in premenopausal women.


Assuntos
Fibras na Dieta/farmacologia , Estrogênios/urina , Óleo de Semente do Linho/farmacologia , Pré-Menopausa , Adolescente , Adulto , Quimioprevenção , Estudos Cross-Over , Dieta , Fibras na Dieta/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Óleo de Semente do Linho/administração & dosagem
16.
Cancer Epidemiol Biomarkers Prev ; 9(10): 1113-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11045796

RESUMO

Dietary estrogens, such as lignans, are similar in structure to endogenous sex steroid hormones and may act in vivo to alter hormone metabolism and subsequent cancer risk. The objective of this study was to examine the effect of dietary intake of a lignan-rich plant food (flaxseed) on urinary lignan excretion in postmenopausal women. This randomized, cross-over trial consisted of three 7-week feeding periods during which 31 healthy postmenopausal women, ages 52-82 years, consumed their habitual diets plus 0, 5, or 10 grams of ground flaxseed per day. Urine samples collected for 2 consecutive days during the last week of each feeding period were analyzed for lignan content (enterodiol, enterolactone, and matairesinol) by isotope dilution gas chromatography/mass spectrometry. Compared with the 0-gram flaxseed diet, consumption of 5 or 10 grams of flaxseed significantly increased excretion of enterodiol by 1,009 and 2,867 nmol/day, respectively; significantly increased excretion of enterolactone by 21,242 and 52,826 nmol/day, respectively; and significantly increased excretion of total lignans (enterodiol + enterolactone + matairesinol) by 24,333 and 60,640 nmol/day, respectively. Excretion of matairesinol was not significantly altered by flaxseed consumption. Consumption of flax, a significant source of dietary estrogens, in addition to their habitual diets increased excretion of enterodiol and enterolactone, but not matairesinol, in a dose-dependent manner in this group of postmenopausal women. Urinary excretion of lignan metabolites is a dose-dependent biomarker of flaxseed intake within the context of a habitual diet.


Assuntos
Linho , Lignanas/urina , Pós-Menopausa , Idoso , Biomarcadores/análise , Estudos Cross-Over , Dieta , Relação Dose-Resposta a Droga , Feminino , Humanos , Pessoa de Meia-Idade
17.
Cancer Epidemiol Biomarkers Prev ; 3(6): 493-500, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8000300

RESUMO

Higher intakes of vegetables and fruits are associated with a lower risk of certain human cancers. A biomarker of vegetable and fruit intake would be a valuable research tool. A cross-sectional study assessed the association between plasma carotenoid concentrations and intakes of vegetables and fruits. Plasma carotenoids (alpha-carotene, beta-carotene, lutein, beta-cryptoxanthin, and lycopene) were measured in 50 male and 49 female participants, aged 18-37 years, with a wide range of habitual vegetable and fruit intakes. Dietary intakes were assessed via a food frequency questionnaire. Intake of vegetables and fruits and high carotenoid foods were measured. The sum of the plasma carotenoids (excluding lycopene) was highly correlated with intake of total vegetables and fruits (r = 0.59). Of the individual plasma carotenoids, plasma alpha-carotene had the highest correlation with intakes of both total vegetables (r = 0.50) and total fruits (r = 0.58). Intakes of foods with high carotenoid contents were correlated with their corresponding plasma concentrations as follows: high beta-carotene foods (r = 0.41); high lutein foods (r = 0.46); and high lycopene foods (r = 0.11). Multiple regression analyses showed that intake of total vegetables and fruits was the most significant determinant of each plasma carotenoid except lycopene. The utility of combining the plasma carotenoids as biomarkers of vegetable and fruit intake was assessed by a stepwise regression of total vegetable and fruit intake on plasma carotenoids. Significant determinants of intake of total vegetables and fruits were alpha-carotene, beta-cryptoxanthin, lutein, and energy intake (R2 = 0.53).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Biomarcadores/sangue , Carotenoides/sangue , Dieta , Frutas , Verduras , Adolescente , Adulto , Carotenoides/análogos & derivados , Colesterol/sangue , Estudos Transversais , Criptoxantinas , Ingestão de Energia , Comportamento Alimentar , Feminino , Humanos , Luteína/sangue , Licopeno , Masculino , Análise de Regressão , Fatores Sexuais , Vitamina E/sangue , Xantofilas , beta Caroteno
18.
Cancer Epidemiol Biomarkers Prev ; 8(8): 699-707, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10744130

RESUMO

Dietary isoflavone and lignan phytoestrogens are potential chemopreventive agents. This has led to a need to monitor exposure to these compounds in human populations and to determine which components of a mixed diet contribute to the exposure. Typically, urinary isoflavonoid excretion is associated with soy consumption and that of lignans is associated with whole grains. However, other plant foods are known to contain phytoestrogen precursors. The purpose of this study was to examine the association between urinary isoflavonoid and lignan excretion and intakes of vegetables and fruits (V&F). Isoflavonoids (genistein, daidzein, O-desmethylangolensin, and equol) and lignans (enterolactone, enterodiol, and matairesinol) were measured in urine collected for 3 days from 49 male and 49 female volunteers (age, 18-37 years) reporting a wide range of habitual V&F intakes. Dietary intakes were assessed using 5-day diet records and a food frequency questionnaire. V&F groupings (total V&F, total V, total F, soyfoods, and V&F grouped by botanical families) were used to assess the relationship between V&F intake and urinary isoflavonoid and lignan excretion. Pearson correlations were performed. Intake of soyfoods was correlated significantly with urinary genistein (r = 0.40; P = 0.0001), O-desmethylangolensin (r = 0.37; P = 0.0002), daidzein (r = 034; P = 0.0007), and the sum of isoflavonoids (r = 0.39; P = 0.0001). There was no association between equol excretion and soy intake or between the isoflavonoids and any other V&F groupings. In addition, isoflavonoid excretion was correlated positively with intake of high-fat and processed meats, particularly among men who did not consume soy. This suggests that, even in the United States, on a Western diet, soyfoods are the primary contributors to isoflavone intake; however, additional "hidden sources" of soy may also contribute to exposure. In contrast, a variety of fiber-containing foods contributed to lignan excretion; the sum of the urinary lignans, enterodiol, enterolactone, and matairesinol, was associated with intake of total F (r = 0.27; P = 0.008), total V&F (r = 0.25; P = 0.01), soyfoods (r = 0.28; P = 0.006), and dietary fiber (r = 0.36; P = 0.0003). Overall, urinary phytoestrogens (isoflavonoids + lignans) were significantly higher in "high" compared with "low" V&F consumers. Compared with the "low" V&F group, the "high" group consumed diets that were, on average, higher in fiber and carbohydrate and soyfoods and lower in fat; thus, the urinary phytoestrogens may also be a useful marker of healthier dietary patterns.


Assuntos
Frutas , Isoflavonas/urina , Lignanas/urina , Proteínas de Soja , Verduras , Adolescente , Adulto , Estudos Transversais , Fibras na Dieta , Feminino , Humanos , Masculino
19.
Artigo em Inglês | MEDLINE | ID: mdl-7549803

RESUMO

Epidemiological studies have demonstrated that diets high in vegetables and fruit are associated with a decreased risk of cancer and, possibly cardiovascular disease. Certain constituents of vegetables and fruit inhibit the in vitro activity of platelet-derived growth factor (PDGF), a potent mitogen implicated in both cancer and cardiovascular disease. Few studies have measured PDGF in relationship to diet in vivo. Specifically, there are no data regarding the changes in PDGF levels of mitogenic activity after a dietary intervention. In this study, 19 young, healthy individuals consumed four (9-day) experimental diets in random order: (a) control diet alone; (b) control diet plus carotenoid-rich vegetables; (c) control diet plus cruciferous vegetables; and (d) control diet plus soy foods. Compared to the control diet, there was a significant elevation in PDGF-AB serum levels when the individuals were consuming the soy diet (P = 0.016). Increased PDGF-AB levels were also noted for the carotenoid diet. There was no change from baseline levels when individuals were consuming the cruciferous diet. Overall, mitogenic activity did not change on any of the experimental diets. This study suggests that high soy and carotenoid diets increase serum levels of PDGF-AB. This may represent an additional mechanism by which diet influences individual risk of cancer; further investigation into the role of diet and growth factors is warranted.


Assuntos
Dieta , Fator de Crescimento Derivado de Plaquetas/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/prevenção & controle , Células Cultivadas , Estudos Cross-Over , Feminino , Fibroblastos/citologia , Humanos , Masculino , Mitose/fisiologia , Neoplasias/sangue , Neoplasias/prevenção & controle , Fatores de Risco , Verduras
20.
Artigo em Inglês | MEDLINE | ID: mdl-7549804

RESUMO

High vegetable intake has been associated with a decreased risk for various human cancers in epidemiological studies. Carotenoids are plant compounds that may both possess chemopreventive activity and be useful biomarkers of vegetable and fruit intake. Nineteen men and women were randomized into a controlled cross-over feeding study to measure the effect of vegetable intake on plasma carotenoid concentrations. Participants consumed each of 4 experimental diets for 9 days. The control diet consisted of commonly consumed foods and was essentially carotenoid free. High vegetable diets (carotenoid, cruciferous, and soy) consisted of the control diet plus carrots and spinach (carotenoid), broccoli and cauliflower (cruciferous), and tofu and FriChik (soy). Plasma carotenoid concentrations were highest on the carotenoid and cruciferous diets. When compared to the control, mean plasma alpha-carotene, beta-carotene, and lutein concentrations were 5.2, 3.3 and 2.2 times higher on the carotenoid diet, respectively (P < 0.001). Mean plasma lutein concentrations were 2.1 times higher on the cruciferous versus the control diet (P < 0.001). There were no differences between diets in plasma beta-cryptoxanthin and lycopene concentrations. These data indicate that plasma alpha-carotene, beta-carotene, and lutein may be useful biomarkers of carotenoid-rich food intake and that lutein may act as an intake biomarker of commonly consumed vegetables in the Cruciferae family. These findings should prove useful in undertaking dietary intervention trials because they suggest the feasibility of monitoring intake of some plant foods and of distinguishing among plant food groups.


Assuntos
Carotenoides/sangue , Ingestão de Alimentos , Verduras , Adulto , Análise de Variância , Biomarcadores/sangue , Estudos Cross-Over , Feminino , Humanos , Masculino , Neoplasias/prevenção & controle , Fatores de Risco
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